Hair loss treatments, particularly finasteride, raise concerns about erectile dysfunction amongst men in the UK. Finasteride works by reducing dihydrotestosterone (DHT), the hormone responsible for male pattern baldness, but this hormonal effect prompts questions about sexual side effects. Clinical trials show erectile dysfunction occurs in approximately 1.3% of men taking finasteride versus 0.7% on placebo. The MHRA has issued warnings about potential persistent sexual dysfunction even after stopping treatment. Alternative options like topical minoxidil do not affect hormones and carry minimal sexual side effect risk. Understanding the evidence helps you make informed decisions about balancing hair loss treatment with sexual health priorities.

Understanding Hair Loss Treatments and Sexual Side Effects

Hair loss, particularly male pattern baldness (androgenetic alopecia), affects millions of men in the UK. Whilst various treatments exist to slow or reverse hair loss, concerns about potential sexual side effects—especially erectile dysfunction—frequently deter men from seeking treatment. Understanding the relationship between hair loss medications and sexual function is essential for making informed decisions about your health.

The most commonly prescribed oral medication for male pattern baldness is finasteride (1mg tablets). Finasteride works by inhibiting the enzyme 5-alpha reductase, which converts testosterone into dihydrotestosterone (DHT). Since DHT is the primary hormone responsible for shrinking hair follicles in genetically susceptible men, reducing DHT levels can slow hair loss and promote regrowth. However, because finasteride affects hormone metabolism, questions naturally arise about its impact on sexual function.

Other hair loss treatments include minoxidil (a topical solution applied directly to the scalp), which works by opening potassium channels and causing vasodilation, though its exact mechanism is not fully understood. Unlike finasteride, it does not affect hormone levels. Additional options include low-level laser therapy, platelet-rich plasma (PRP) injections, and hair transplant surgery. Each treatment has a different mechanism of action and side effect profile.

This article examines the evidence surrounding hair loss treatments and erectile dysfunction, focusing primarily on finasteride whilst also discussing alternative options. Understanding both the benefits and potential risks allows you to have informed discussions with your GP or dermatologist about the most appropriate treatment for your individual circumstances.

Does Finasteride Cause Erectile Dysfunction?

Finasteride's association with erectile dysfunction has been documented in clinical trials and post-marketing surveillance, though the relationship remains complex. The medication's Summary of Product Characteristics (SmPC), approved by the MHRA, lists sexual side effects including decreased libido, erectile dysfunction, and ejaculation disorders as known adverse reactions.

In the clinical trials that led to finasteride's approval, sexual side effects were reported in a small percentage of men. According to the UK SmPC for finasteride 1mg, erectile dysfunction occurred in 1.3% of men taking finasteride compared to 0.7% on placebo. The most commonly reported issues included reduced sexual desire, difficulty achieving or maintaining erections, and decreased ejaculate volume. In most men who experienced these effects during trials, symptoms resolved either whilst continuing treatment or after discontinuation.

Importantly, the MHRA has issued a Drug Safety Update highlighting that sexual dysfunction may persist after stopping finasteride. The MHRA also warns about the risk of depression and suicidal thoughts with finasteride use. Patients should be provided with a patient alert card discussing these risks before starting treatment.

The mechanism by which finasteride might affect sexual function relates to its reduction of DHT levels. Whilst DHT is primarily known for its role in hair loss and prostate enlargement, it also contributes to sexual function, though testosterone remains the predominant sex hormone. By inhibiting 5-alpha reductase, finasteride reduces DHT by approximately 70% in the scalp and serum, which may affect some men's sexual response.

The nocebo effect—where negative expectations contribute to experiencing side effects—may play a role in some cases. Research has shown that men who are aware of potential sexual side effects before starting finasteride may report them more frequently. However, this doesn't diminish the reality of symptoms for those who experience them. If you're considering finasteride, discussing these concerns openly with your healthcare provider can help you make a balanced decision based on your individual risk factors and priorities.

How Common Are Sexual Side Effects with Hair Loss Medication?

Determining the true incidence of sexual side effects from hair loss medications requires examining multiple sources of evidence. According to the UK SmPC for finasteride 1mg, erectile dysfunction occurred in 1.3% of men taking finasteride compared to 0.7% on placebo during clinical trials. Decreased libido was reported in 1.8% versus 1.3% on placebo. Post-marketing surveillance has continued to identify sexual dysfunction as an important adverse effect.

A review of clinical data suggests that sexual adverse events occur in approximately 2-4% of men taking finasteride for hair loss. Most men who experience sexual side effects find they are mild to moderate in severity and often resolve with continued treatment as the body adjusts to the medication. However, the MHRA has highlighted that some men may experience persistent sexual dysfunction even after stopping finasteride.

For topical minoxidil, sexual side effects are exceptionally rare because the medication acts locally on the scalp with minimal systemic absorption. Minoxidil works through vasodilation and potassium channel effects that do not interfere with hormonal pathways involved in sexual function. Clinical trials and post-marketing surveillance have not established a link between topical minoxidil and erectile dysfunction.

It's important to contextualise these figures: erectile dysfunction is relatively common in the general population, affecting approximately 40% of men over 40 to some degree, with prevalence increasing with age according to NHS data. Factors including stress, anxiety, cardiovascular disease, diabetes, obesity, smoking, and alcohol consumption all contribute significantly to erectile problems. When men starting hair loss treatment experience erectile dysfunction, it may be coincidental rather than causally related to the medication. Nonetheless, any new or worsening sexual symptoms warrant discussion with your GP to determine the underlying cause and appropriate management.

If you experience any suspected adverse effects from medication, you can report them through the MHRA Yellow Card Scheme, which helps monitor medication safety.

What to Do If You Experience Erectile Dysfunction

If you develop erectile dysfunction whilst taking hair loss medication, several steps can help you address the issue effectively. Do not stop your medication without medical advice unless you develop depression or suicidal thoughts—in which case, stop finasteride immediately and seek urgent medical attention, as advised by the MHRA.

First, consult your GP or the prescribing clinician. They will take a thorough history to determine whether the erectile dysfunction is likely related to finasteride or due to other factors. Your doctor may ask about:

• The timing of symptom onset relative to starting medication

• The severity and frequency of erectile difficulties

• Other medications you're taking (some can contribute to erectile dysfunction)

• Lifestyle factors including stress, sleep, alcohol intake, and smoking

• Underlying health conditions such as diabetes, hypertension, or cardiovascular disease

• Psychological factors including anxiety, depression, or relationship issues

Your GP may recommend temporarily discontinuing finasteride to see if symptoms improve. Sexual side effects typically resolve within weeks to months after stopping the medication, though some men report persistent symptoms. If discontinuation leads to improvement, you and your doctor can discuss whether to try restarting at a lower dose, switching to alternative treatments, or accepting hair loss as a trade-off for restored sexual function.

If erectile dysfunction persists after stopping finasteride or appears unrelated to the medication, your GP may arrange investigations including blood tests (morning testosterone levels between 9-11am with repeat if low, HbA1c, lipids, and thyroid function) and blood pressure measurement. NICE guidance recommends addressing cardiovascular risk factors, as erectile dysfunction often serves as an early warning sign of cardiovascular disease.

Treatment options for erectile dysfunction include lifestyle modifications (exercise, weight loss, reducing alcohol, stopping smoking), psychological support (if anxiety or relationship issues contribute), and phosphodiesterase-5 inhibitors such as sildenafil. Generic sildenafil is available on NHS prescription, and Viagra Connect (sildenafil 50mg) can be purchased from pharmacies after a pharmacist assessment. Your GP can guide you through these options based on your individual circumstances.

Alternative Hair Loss Treatments Without Sexual Side Effects

For men concerned about potential sexual side effects or those who have experienced problems with finasteride, several alternative hair loss treatments are available that do not affect hormonal pathways.

Minoxidil (available as 5% solution or foam) is the most established alternative. Applied directly to the scalp twice daily, minoxidil stimulates hair growth through vasodilation and potassium channel effects. It does not affect DHT or testosterone levels, making sexual side effects extremely unlikely. Minoxidil is available over the counter from pharmacies and has been used safely for decades. Results typically become visible after 3–4 months of consistent use, with optimal effects at 12 months. The main drawbacks are the need for ongoing daily application and potential scalp irritation in some users.

Low-level laser therapy (LLLT) devices, available as handheld combs or caps, use red light to stimulate cellular activity in hair follicles. These devices typically have UKCA/CE marking, though this indicates safety rather than proven efficacy. Some clinical trials have shown modest improvements in hair density with LLLT. These devices have no systemic effects and therefore no sexual side effects, though they can be expensive and require regular use (typically 15–30 minutes several times weekly).

Platelet-rich plasma (PRP) therapy involves drawing your blood, concentrating the platelets, and injecting the plasma into your scalp. Growth factors in platelets may stimulate hair follicles. Evidence for PRP remains limited but growing. This treatment is not routinely available on the NHS and is typically offered by private dermatology clinics. As a procedural treatment using your own blood, PRP has no hormonal effects but carries procedural risks including pain, bruising, and infection.

Hair transplant surgery provides a long-lasting solution by relocating hair follicles from the back of the scalp (where they're resistant to DHT) to thinning areas. Modern techniques like follicular unit extraction (FUE) can produce natural-looking results. Transplants don't prevent further hair loss in untreated areas, so many surgeons recommend combining transplants with minoxidil or other treatments. It's advisable to choose a CQC-regulated provider for this procedure.

Discussing these options with a GP or dermatologist can help you develop a treatment plan that addresses your hair loss concerns whilst respecting your priorities regarding sexual health and overall wellbeing.

Frequently Asked Questions